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Symfony2 – Franz Jordán 2011
}
As a front controller, index.php has taken on an entirely new role, one that includes loading
the core libraries and routing the application so that one of the two controllers
(the list_action() andshow_action() functions) is called. In reality, the front controller is
beginning to look and act a lot like Symfony2's mechanism for handling and routing requests.
Another advantage of a front controller is flexible URLs. Notice that the URL to the blog post
show page could be changed from /show to /read by changing code in only one location.
Before, an entire file needed to be renamed. In Symfony2, URLs are even more flexible.
By now, the application has evolved from a single PHP file into a structure that is organized and
allows for code reuse. You should be happier, but far from satisfied. For example, the "routing"
system is fickle, and wouldn't recognize that the list page (/index.php) should be accessible
also via/ (if Apache rewrite rules were added). Also, instead of developing the blog, a lot of time
is being spent working on the "architecture" of the code (e.g. routing, calling controllers,
templates, etc.). More time will need to be spent to handle form submissions, input validation,
logging and security. Why should you have to reinvent solutions to all these routine problems?
Add a Touch of Symfony2
Symfony2 to the rescue. Before actually using Symfony2, you need to make sure PHP knows how
to find the Symfony2 classes. This is accomplished via an autoloader that Symfony provides. An
autoloader is a tool that makes it possible to start using PHP classes without explicitly including
the file containing the class.
First, download symfony and place it into a vendor/symfony/ directory. Next, create
anapp/bootstrap.php file. Use it to require the two files in the application and to
configure the autoloader: